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G L Adessi

Publications and source records attributed to G L Adessi.

At least 73 records · Page 4Linked to original sources
PubMed1986

A dehydroepiandrosterone sulfatase inhibitory activity in soluble proteins of guinea pig liver.

An inhibitor of microsomal dehydroepiandrosterone sulfatase was found in the soluble fraction of non-pregnant guinea pig liver. The extent of inhibitory effect was dependent on the concentration of soluble proteins. The inhibitor was partly purified by gel permeation and hydroxylapatite chromatography with a purification factor of 16.6. The soluble inhibitor was non-dialyzable, not destroyed by RNase or DNase digestion but totally destroyed by pronase digestion. The inhibitor is a soluble protein with a molecular weight of approximately 17,000 (determined by gel permeation chromatography). Inhibition of microsomal dehydroepiandrosterone sulfatase by the soluble inhibitor is a non-competitive inhibition. From this present finding the question arises whether the inhibitor could be involved in the regulation of the hydrolysis of dehydroepiandrosterone sulfate in the guinea pig liver.

Animals↗
PubMed1986

Free fatty acids and fatty acids of triacylglycerols in normal and hyperkeratotic human stratum corneum.

The content of the free fatty acids and the fatty acids of triacylglycerols has been measured in human plantar stratum corneum from normal and hyperkeratotic subjects with palmoplantar keratoderma. Fatty acids of triacylglycerols in normal tissues showed a characteristic pattern with a relative abundance of short-chain length and unsaturated fatty acids. Free fatty acid fraction was characterized by the predominance of saturated compounds. The relative amount of short-chain and monoene fatty acids in the hyperkeratotic stratum corneum was increased. These results seem to show a defect in the maturation of fatty acids in the living epidermis and present new evidence that the abnormality of lipid metabolism can influence the process of desquamation in stratum corneum.

Adult↗
PubMed1986

Culture of epithelial and stromal cells of guinea-pig endometrium and the effect of oestradiol-17 beta on the epithelial cells.

Epithelial and stromal cells of guinea-pig endometrium were separated by enzymic digestion, isolated by successive centrifugation, and maintained in culture as pure cell types for 5 days on growth medium. On Day 5, ultrastructural studies were performed on the two cell types, demonstrating that epithelial cells can grow as a monolayer composed of cohesive groups of polygonal cells (1.3 X 10(5) cells/cm2), while stromal cells were mostly fibroblastic. The effect of hormones was studied on the epithelial cells in culture. The monolayer was cultured into harvest medium for 3 days to ensure the complete removal of endogenous steroids, then these cells were incubated with 2 X 10(-9) M-oestradiol-17 beta for 3 days. There was a rise in the progesterone receptor level, varying from 1.3 to 10.8 times. The three enzymes known to interfere with oestradiol-17 beta metabolism were present in the epithelial cells grown in our culture conditions. By incubation with oestrone sulphate for 3 days it was demonstrated that, in cultured epithelial cells, oestrone sulphate is converted into oestradiol-17 beta sulphate, and oestrogen sulphates are hydrolysed to active oestrogens.

Animals↗
PubMed1986

[Demonstration of a cytosolic inhibitory of membrane estrone sulfatase activity in guinea pig liver].

Estrone sulfatase is a membrane-bound enzyme hydrolysing estrone sulfate. In normal and pathological tissues, estrone sulfatase is required for the conversion of estrone sulfate into physiologically active estrogens. In the hepatic cytosol of Guinea-pig, we have demonstrated the existence of a soluble inhibitor of uterine and hepatic microsomal estrone sulfatase. This inhibitor has approximatively a molecular weight of 7,600 and acts as a non-competitive inhibitor of estrone sulfatase. It seems to be a soluble intra-cellular effector of membrane-bound estrone sulfatase.

Animals↗
PubMed1985

Estrone- and dehydroepiandrosterone-sulfatase activities in human female epidermis.

Estrone (E1)-sulfatase and dehydroepiandrosterone (DHEA)-sulfatase activities were studied in human female epidermis. Skin specimens were obtained by abdominal or plantar biopsies. The apparent Michaelis-Menten constants for E1 and DHEA sulfatases were 35.2 microM and 8.7 microM, respectively. A substrate inhibition was only observed for DHEA sulfatase. Both sulfatases had an elevated temperature optimum (65 degrees C). The effect of inorganic salts was also tested. In normal epidermis, E1-sulfatase activity was constantly higher than DHEA-sulfatase activity, but no correlation between these activities was observed. On the other hand, E1- and DHEA-sulfatase activities were lower in plantar than in abdominal epidermis. In plantar epidermis of palmoplantar keratoderma, large variations in E1-sulfatase activity, but no significant variation in DHEA-sulfatase activity, were observed. In human epidermis, the findings were consistent with the existence of two different sulfatases: E1 sulfatase and DHEA sulfatase. It would also appear that sulfatase activities are not linked to the abnormal shedding of plantar stratum corneum in palmoplantar keratoderma.

Abdomen↗
PubMed1985

Characterization of a glucocorticoid receptor in neonatal rat mammary gland.

A glucocorticoid receptor has been identified in cytosolic fractions prepared from 4-day old female Sprague-Dawley rat mammary glands at an early resting stage of mammary development. This component sedimented at 10S and 5S on respectively low and high (0.4 M KCl) ionic strength gradients. It bound dexamethasone with a high affinity (Kd approximately 2-6 nM) and a low capacity (N = 300 +/- 100 fmol per mg of proteins or 3.3 +/- 1.3 fmol per micrograms DNA), with a hierarchy of affinity by competition studies dexamethasone greater than corticosterone greater than progesterone greater than R 5020 much greater than Estradiol-17 beta. The characteristics of this glucocorticoid-binding protein are thus very similar to the adult one isolated from adult rat mammary gland.

Animals↗
PubMed1984

Estrone sulfatase activity in normal and abnormal endometrium.

We investigated the activity of estrone sulfatase in normal and pathological endometrium. In normal endometrium, the estrone sulfatase activity [pmol E1 X min-1 X (mg prot)-1] was 23.13 +/- 8.44 (mean +/- SD). An increase (p less than 0.01) of estrone sulfatase activity (62.81 +/- 21.97) was noted in mild endometrial hyperplasia. In focal hyperplasia (when the measurements were performed in the normal endometrial biopsies) such an increase was not noted (19.10 +/- 5.33). Estrone sulfatase activities of moderate hyperplasia (25.30 +/- 11.40) and endometrial neoplasia (30.30 +/- 9.57) were in the same range as in normal endometrium. Treatment with progestagen simultaneously reduced hyperplasia and estrone sulfatase activity. But when morphologically abnormal endometrium persisted after treatment, estrone sulfatase activity remained increased. The increase of estrone sulfatase activity appeared to be specific to mild endometrial hyperplasia. The role of estrone sulfatase in the pathogenesis of endometrial hyperplasia is discussed.

Adult↗
PubMed1984

Estrone and dehydroepiandrosterone sulfatase activities in guinea-pig uterus and liver: estrogenic effect of estrone sulfate.

Estrone and dehydroepiandrosterone (DHA) sulfatase activities were studied in the uterus and liver of female guinea-pigs (albino variety). The two activities were found in particulates, with the highest specific activity in microsomes. The effects of pH, buffers, temperature and the non-competitive inhibition of DHA sulfate on estrone sulfatase provided arguments for the existence of two distinct sulfatases. However, acrylamide gel electrophoresis of the solubilized microsome sulfatases gave a single peak for the two activities. In the uterus, the apparent Km of estrone and DHA sulfatases were 26.4 and 15.6 microM. Solubilized microsomal estrone sulfatase was inhibited by unconjugated steroids. The apparent Km of estrone sulfatase in liver was 10.7 microM. Estrone and DHA sulfatase activities were consistently lower in liver than in uterus and no DHA sulfatase activity was detected in fetal liver. In the uterus, the same sulfatase activities were found in female fetuses, castrated or mature females. Estrone sulfatase was significantly increased in the uterus of pregnant females (60-65 days gestation). Estrone sulfate was injected in vivo into mature castrated females. A significant increase in uterine weight and in uterine progesterone receptors was observed. The cytosol progesterone receptors were characterized by their Kd (1.40 nM) and by sucrose density gradient. It is concluded that the variations of estrone sulfatase activity in target tissues like the uterus may control the intracellular levels of biologically active estrogens.

Animals↗
PubMed1984

Steroid sulfatase activities in normal and cirrhotic livers and plasma levels of estrone sulfate, estrone and estradiol-17 beta in men.

Estrone and dehydroepiandrosterone (DHEA) sulfatases were studied in livers of normal and cirrhotic men. Their Km were 3.2 microM and 1.2 microM respectively. The microsomal sulfatases were solubilized by Miranol H2M and ultrasound. After gel filtration, the soluble material gave a single peak of activity for both substrates with a molecular weight of approximately 330,000. In terms of pmol of product.min-1 per mg of fresh tissue, the mean (+/- SD) values of estrone and DHEA sulfatase activities were lower in cirrhotic livers [(n = 7) (4.09 +/- 2.90 and 0.38 +/- 0.20)] than in normal livers [(n = 13)(8.29 +/- 4.00 and 0.69 +/- 0.20)]. The differences were statistically significant : p less than 0.03 for estrone sulfatase and p less than 0.01 for DHEA sulfatase. In cirrhotic men, the mean level of plasma estrone is increased whereas that of estrone sulfate is decreased. The variations may be related to the decrease of serum albumin in cirrhotic subjects.

Adult↗
PubMed1984

Beta-lactamase with high molecular weight: evidence for an interaction with neuraminic acid-containing structures.

The constitutive beta-lactamase activity from Escherichia coli strain J53 (R6K) was separated into two fractions by gel filtration. One fraction (F') had a well known molecular weight 21,000; the other (F) had a molecular weight greater than 70,000. The F beta-lactamase gave a fraction similar to F' after neuraminidase treatment followed by gel filtration, suggesting that beta-lactamase molecules may be associated with neuraminic acid-containing structures. Such complexes could be an explanation for the multiple bands given in isoelectrofocusing of crude enzymatic extracts.

Chemical Phenomena↗
PubMed1984

[Fatty acids in normal and pathological stratum corneum of humans].

Fatty acids of triacylglycerols and free fatty acids have been studied in normal and hyperkeratotic human plantar stratum corneum. The results emphasize a decrease of long-chain fatty acids (greater than C18) in the hyperkeratotic tissues. Possible explanation for these findings are discussed in relation to the fatty acids metabolism in living epidermis.

Chromatography, Gas↗
PubMed1984

Estrone and dehydroepiandrosterone sulfatase activities and plasma estrone sulfate levels in human breast carcinoma.

The activity of the two membrane-bound sulfatases, estrone and dehydroepiandrosterone sulfatases, are reported in human breast carcinoma tissues. In 21 tested tumors (12 from post-menopausal women and 9 from nonmenopausal women), the two sulfatases were consistently present. The apparent Km values for estrone and dehydroepiandrosterone sulfatases were, respectively, 6.8 and 14.9 microM. In terms of maximal velocity, the sulfatase activities are not correlated to the estrogen or progesterone receptor status of the tumors or to the hormonal status of the donors. It may be concluded that these two activities are not hormone dependent. Estrone sulfate, the substrate of estrone sulfatase, has been measured in plasma of postmenopausal women. The mean levels (nmol/liter) of plasma estrone sulfate were compared in post-menopausal women with (n = 51) or without (n = 39) breast cancer. For the first age group (48 to 55 years old), no statistically significant difference in these levels was observed [1.91 +/- 1.06 versus 1.50 +/- 1.04 (mean +/- t0.95 (Formula: see text) S.E.)]. For the two other age groups (56 to 65 and 66 to 80 years of age), the differences were statistically significant [1.46 +/- 0.43 versus 0.77 +/- 0.21 (p less than 0.02) and 1.77 +/- 0.53 versus 0.81 +/- 0.22 (p less than 0.01)]. The usefulness of plasma estrone 3-sulfate levels as an indicator of the real estrogen status of postmenopausal women is discussed.

Breast Neoplasms↗
PubMed1983

Estrone and dehydroepiandrosterone sulfatase activities in normal and pathological human endometrium biopsies.

The properties of estrone (E1) and dehydroepiandrosterone (DHEA) sulfatase activities are reported. Endometrial biopsy specimens were obtained using a Novak curette. Cycle stage was assessed from histological dating of endometrium, plasma estradiol and progesterone levels, and patient history. Both sulfatases are membrane-bound enzymes. The optimum pHs in Tris-HCl buffer were 6.5 for E1 sulfatase and 7.3 for DHEA sulfatase. Lowest activities and different optimum pHs were obtained with imidazole, maleate, or acetate buffers. DHEA sulfatase is more sensitive to thermal inactivation than E1 sulfatase. From kinetic studies, apparent Km values of 3.1 microM for E1 sulfatase and 5.7 microM for DHEA sulfatase were calculated. Noncompetitive inhibition of E1 sulfatase by DHEA sulfate and of DHEA sulfatase by E1 sulfate were demonstrated. The effects of inorganic ions and unconjugated steroids were also tested. These results are consistent with two different activities hydrolyzing E1 or DHEA sulfates. Neither activity varies during normal menstrual cycles nor is not correlated to plasma progesterone or 17 beta-estradiol levels. An isolated increase in E1 sulfatase occurred in the proliferative phase of irregular menstrual cycles, postantibiotic-treated salpingitis, or hyperplastic endometrium.

Dehydroepiandrosterone↗
PubMed1983

Estrone sulfate concentrations in plasma of normal individuals, postmenopausal women with breast cancer, and men with cirrhosis.

Estrone sulfate is quantitatively the most important estrogen in plasma. A method for its determination in human plasma is described, and the precision, accuracy, sensitivity, and specificity are defined. Free steroids were extracted from plasma with diethyl ether and steroid sulfates were isolated with use of Vlitos' reagent (methylene blue in dilute H2SO4/Na2SO4 solution). After enzymic hydrolysis, estrone was isolated by chromatography on Celite and measured by radioimmunoassay. The mean concentrations (nmol/L +/- 1 SD) of estrone sulfate were 2.51 +/- 0.90 for plasma from 13 women in follicular phase, 5.33 +/- 1.55 for 17 women in luteal phase, 0.89 +/- 0.60 for 44 postmenopausal women, and 0.96 +/- 0.43 for 24 postmenopausal women with breast cancer. Results for postmenopausal women with or without breast cancer did not differ significantly. For 13 normal men, estrone sulfate concentrations were 2.62 +/- 0.79 nmol/L, and for a group of 19 cirrhotic men the mean value was 1.43 +/- 0.95 nmol/L, significantly lower than normal.

Adult↗
PubMed1983

[Clinical, hormonal and celioscopic examination of the corpus luteum in sterility without pelvic lesions].

58 sterile women who had perfect biphasic temperature curves through their menstrual cycles were examined by laparoscopy in the luteal phase of the cycle. No pelvic lesion was found. In 21 patients it was seen that the follicle had not ruptured (the so-called non-ruptured follicle syndrome). In a further 9 cases there was no luteal follicle to be seen on the surface of the ovary. The respective values of the plasma biochemical parameters which reflect ovarian secretion in the luteal phase are discussed; the importance of oestrogen secretion at the 6th day of the luteal phase is emphasized. It has been shown that there are significant statistical differences in the levels of oestradiol in the blood.

Corpus Luteum↗
PubMed1981

[Evidence, in vitro, of estrone and estradiol-17 beta 3-sulfoconjugate hydrolysis in the uterus of pregnant guinea pigs].

The metabolism, in vitro, of [6,7-3H]-oestrone-3-sulfate and [6,7-3H]-oestradiol-17beta-3-sulfate by the uteri of pregnant female Guinea-Pigs has been studied using 900 g supernatants. A hydrolysis of the sulfate moiety was observed: 35% of the radioactivity was recovered in the unconjugated fractions after 1 hr. of incubation. Gluruconide oestrogens were also recovered but the rate of synthesis was very low (3.6% after 1 hr.). OEstrone and oestradiol-17beta have been identified in unconjugated, glucuro and sulfo-conjugated fractions after incubation with the tritiated oestrogen sulfates.

Animals↗